Mark of the Wild (MotW) is a druidbuff spell learned at level 62. It can be cast on yourself and friendly players. It increases the target's strength, agility, and intellect. Since the spell has a very long duration, it is standard practice to keep the spell up on all party members while in a group.

A Druid should always have Mark of the Wild on themselves, and be sure that every member of their group has been buffed too (including any pets).

If you have Mana to spare while soloing, any nearby friendly player will appreciate and benefit from this ability. It will encourage those classes with buffs to reciprocate.

Trivia

According to the World of Warcraft pen-and-paper RPG [1], Mark of the Wild is a druidic spell shared by druids, hunters, and elven rangers. By channeling the wild into a willing receptacle a caster can fill an ally with the feral grace and swiftness of the dire beasts of the Emerald Dream. Druids know two related druid-only spells called Greater Mark of the Wild, and Lesser Mark of the Wild.

Cataclysm

Pushed from a level one- to a level 30-ability, Mark of the Wild will no longer boost Spirit with Cataclysm.[2] Furthermore it will increase the friendly target's Strength, Agility, Stamina, and Intellect by 5%, and all magical resistances by 65 (at level 80), for 1 hour. [3] It will be identical to Blessing of Kings and will not stack with it. The specific resistance amount given by the buff is equal to half the target’s level up to (and including) level 70, and gives 3 for every level 71 and up – at 68 and 69 it gives 34 resistance, at 70 it gives 35, and at 71 it gives 38.

Mark of the Wild gives 97 resistance to NPCs of Level 85, meaning this will likely be the new highest value it can provide to a player controlled character when the level cap is raised. When cast on Tyrande Whisperwind, a level ?? boss, this buff gives 117 resistance.

Patch changes

Patch 5.3.0 (21-May-2013): Mark of the Wild had its mana cost reduced to 5%, down from 10%.

Patch 5.2.0 (5-Mar-2013): Revive and Mark of the Wild now cost 55% less mana.

/Patch 4.0.1 (12-Oct-2010):[Mark of the Wild] no longer increases armor and spirit. If player is in a group or raid and it is cast in a group/raid member, it will affect all members. Length increased from 30 minutes to 1 hour. Group version [Gift of the Wild] has been removed. Mana cost reduced from 24% to 14% of base mana. Associated talent Improved Mark of the Wild has been removed.